So very, very lonely...

So, I'm sixteen and at school I mostly hang out with two other girls and some other people at times. However, now that it is summer break we don't see each other on a regular anymore and when I try to make plans with them they pretty much just ignore me. It hurts because I don't really have anybody else and I really thought we were close. I always knew that they spent more time with each other than with me since they have more similar interests but still.

Please help and give advice. So far I've spent the summer alone and I don't want that anymore.